Chemical composition of cloud and rainwater at a high-altitude mountain site in western India: source apportionment and potential factors.

This study focuses on the chemical composition of cloud water (CW) and rainwater (RW) collected at Sinhagad, a high-altitude station (1450 m AMSL) located in the western region of India. The samples were collected during the monsoon over two years (2016-2017). The chemical analysis suggests that the concentration of total ionic constituents was three times higher in CW than in RW, except for NH (1.

Aerosol-CCN characteristics and dynamics associated with a pre-monsoon dust storm over a high-altitude site in Western Ghats, India.

Aerosol-CCN characteristics and dynamics during a pre-monsoon dust storm (April 6-11, 2015) over a high-altitude site ((17.92°N, 73.66°E, and 1348 m above mean sea level (MSL)) in Western Ghats, India, has been studied using ground-based observations, satellite, and reanalysis datasets.

Characteristics of elevated aerosol layer over the Indian east coast, Kattankulathur (12.82N, 80.04°E): A northeast monsoon region.

The elevated aerosol layer (EAL) plays a vital role in weather and climate by modifying the Earth's radiation budget. In the present study, the EAL occurrence and its characteristics in the pre-monsoon season using micropulse lidar (MPL) observations during 2016-2018 and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) during 2007-2018 over Kattankulathur is being reported. We have collected 147 days (101 cases) of MPL (CALIPSO) observations during clear sky conditions in the pre-monsoon 2016-2018 (2007-2018), out of which EAL is observed for 56 days (61 cases).

Compensatory effect of biomass burning on black carbon concentrations during COVID-19 lockdown at a high-altitude station in SW India.

The characteristics of black carbon (BC) aerosols, their sources, and their impact on atmospheric radiative forcing were extensively studied during the COVID-19 lockdown (28th March-31st May 2020) at a high-altitude rural site over the Western Ghats in southwest India. BC concentration and the contribution of BC originating from biomass burning (BC) estimated from the aethalometer model during the lockdown period were compared with the same periods in 2017 and 2018 and with the pre-lockdown period (1st February to March 20, 2020). BC concentrations were 44, 19, and 17% lower during the lockdown period compared with the pre-lockdown periods of 2020 and similar periods (28th March to 31st May) of 2017 and 2018, respectively.

Seasonal characteristics of boundary layer over a high-altitude rural site in Western India: implications on dispersal of particulate matter.

The temporal variability of the planetary boundary layer height (PBLH) over Mahabaleshwar was studied for a period of 1 year from 1 December 2015 to 30 November 2016 using microwave radiometer (MWR) observations. The PBLH over Mahabaleshwar was found to be the highest during the pre-monsoon (March-May) season and lowest during the winter (December-February) season. The seasonal mean of PBLH was estimated to be 339±88 m during winter, 485±70 m during pre-monsoon, 99±153 m during monsoon, and 438±24 m during post-monsoon season.

Sub micron aerosol variability and its ageing process at a high altitude site in India: Impact of meteorological conditions.

The effect of relative humidity and temperature on the submicron aerosol variability and its ageing process was studied over a high altitude site, Mahabaleshwar in south-west India. The mass composition of non-refractory particulate matter of 1 μm (NR-PM) size was obtained using Time of Flight Aerosol Chemical Speciation Monitor (ToF-ACSM) along with the measurements on a few trace gases during winter (December 2017-February 2018) and summer season (20th March - 5th May 2018). Sulfate exhibited strong dependence on the relative humidity (RH) as its mass fraction increased with the increase in RH.

Black carbon: source apportionment and its implications on CCN activity over a rural region in Western Ghats, India.

This study presents the characteristics of black carbon aerosol (BC) over a high-altitude site, Mahabaleshwar during the monsoon season. The mass concentration of BC exhibits a morning peak and a daytime build-up with a mean mass concentration of 303 ± 142 ng m. The simultaneous measurements of aerosol particle number concentration (PNC), cloud condensation nuclei concentration (CCN), and non-refractory particulate matter less than 1 μm size (NR-PM) were also made by using a Wide-Range Aerosol Spectrometer (WRAS), CCN counter and Aerosol Chemical Speciation Monitor (ACSM) respectively.